Enhancing resolution of delta sigma modulator using 1-bit adaptive DAC

Delta sigma modulators perform high resolution data conversion using oversampling and noise shaping technique. Three factors must be taken into account for designing the modulator, namely the oversampling ratio, the order of the modulator, and the number of bit of the quantizer used. By configuring these factors, the resolution of the modulator can be determined. This paper introduces briefly a new concept of enhancing the resolution of the first order modulator by implementing a 1-bit adaptive DAC as the quantizer. This method simply divides the total dynamic range of the modulator into several layers of smaller dynamic range. By making 2ⁿ layers, an additional of n bit resolution can be achieved.